Combination pilot and vaporizing device for horizontal pot type burners



March 28, 11950 E. H. STEMPEL ET AL COMBINATION PILOT AND VAPORIZING DEVICE FOR HORIZONTAL POT TYPE BURNERS 2 Sheets-Sheet 1 Filed. Oct. 15, 1945 Mmch 2, 1950 E. H. STEMPEL ET AL COMBINATION PILOT AND VAPORIZING DEVICE FOR HORIZONTAL POT TYPE BURNERS 2 Sheets-Sheet 2 Filed Opt. 15, 1945 izverz/iors Patented Mar. 28, 1950 GQ YLBIN I ON ZI ANDV- R. Z'I XG DEVICE FOR -HORIZONTAL POT TYPE Eiiward n' stem eland Mailis-LuNel'son, Albert Lea, Minin, assignors to America'nGas Machine Company, Albert Lea, Minn.,- a corporation-of Minnesota a plicatibn'oewber'ls, 1945, SerialNo. 622,238

v 4C1aims. 1 l his invention relates to liquid fuel burners 'of the so-called p'ot type and particularly, to a combination pilot and'vaporizing device fo'r such burners.

It is an objectof our- -present invention 'to' provide a simplified and highly eflicientcombination pilot and vaporizing device particularly-adapted, but not restricted to horizontal pot "type oil burners.

Another object is' the provision of a combination pilot and vaporizing device of the -c'la'ss described, whe'reins'a highly efiicient admixture and combustion of trial and air is ob'tain'edon pilot :fiameand-on-a variety of different flame settings.

-It:1's a turther'object toprovide a combination .pilot and vaporizing device for p'ot' type burners which will cause a vaporized mixture, during 'heating operation of the' burner, to be discharged within the pot circumferentiall-y therein' Whereby a very efiicient secondary mixture of additional air is efiected before combustion takes place.

A further and more specific object-is 'the provision of a simplified :device of the class described wherein aL-porti'o'n 0f the peripheral wall of the burner pot in itself con'stitutes thazair adini's 6h means and afwall of 'the pilot-housing, the remainder of the pilot and vaporizingstriictu're being, formed by a shell or receptacle fmounted against'a portion of said peripheral wall.

, These and other objects and advantages --of our invention will be more apparent f-rom the following description made in connection with the accompanying drawings, wherein like-reference characters reier to the same parts throughout the 'severalviews and in which:

Fig. 1 is a vertical'section takenaxially through an embodiment of our-invention,applied to-such a device as a floor furnace;

Fig. 2 is a cross section taken on the line i=2 main combustion-chambrC having mounted within one end thereof,- a horizontally disposed cylindrical casing l'l constructed of suitable ma;- terial such as sheet metal, which,-'as shown, extends inwardly at one end past "the vertical par tition l2 defining one wall of the combustion chamber and which at-its op'posit'e end is abutted against a vertical wall 13 constituting, in the floor 'furnao'e illustrated; the exter ior wall-thereof. Itwill, of 'c'ourse, be understood that any suitable-means may beutilized for 'securing the casing 11 to the body of th8-h2tt8r or furnace. shown, we provide the 'casing H with an intermediately disposed, outwardly pressed bead 'I lu. by which the'casing isclamped in a circular aperture formed iii-partition 1-2 and is mainly sup; ported by said partition and the bottom l2bof the combustion chamber. To facilitate such mounting and clamping action the 'apertured casing-receiving portion "of partition I2 is preferably provided with-a turned flange [2a adapted to be engaged at its outer edge against the casing bead Ha, and a clamping ring 14 of angle iron construction surrounds casing H and is clamped hy bolts I5 against the bead Ha =threadedly se cured to'thepartition 12-. -A's-s'ho'wn, at thebottoinof the-casing, we utilizeadeinfdrcin'gchaniiel mehiberfiflto support the lowerspa'rt creasing H.

" Easing H has concentrically mounted thereon, a horizontalfpot type burner comprising a ci'r cumferential or peripheral wall 1'6 preferably constructed of suitable sheet metal and spaced 'a short distance within cylindrical casing H to provide an annular air chamber surrounding-the burner. The peripheral wall, as is common in burners of this type, is provided With 'a multi- Zplicity *of spacedair admission portsor apertures Hia which as shown, are arranged in alter nately staggered circumferential rows. The rear end of the pot burner is'preferably but not meessarily closed by a -circular Vertical wall H 8.5 shown, having an outtur hed flange that telescopes within the'o'uter end "Ofburner'caSing l6 and may be removably -secured thereto 'by one'or more bolts or screws Ha.

At the-inner or'forward end of the pot burner, a flame ring 18 is. provided of considerablysmal-ler internal diameter than that of the casing '0r=peripheral wall [6 and asshowmsecuredto'a flanged ring and closure member 1'9; the outturnedn-ange of which is telescopedwithi-n the forward end of cylindrical casing II and welded or otherwise fixed thereto-the body 'of which extends-between theinner periphery of casing H and the marginal edge of flame ring l8 to close the annular air chamber defined between the pot burner and the casing l l and to further constitute a supporting means fOr the flame ring and the casing l6 of the burner. A secondary air admission ring 20 is secured at its inner marginal portion to closure member l9 and to flame ring I8 as by threaded bolts la and has a rearwardly turned attachment flange 20a which as shown, is telescoped over the forward annular edge of the circumferential wall It of the burner and welded or otherwise rigidly secured thereto. The ring 20 in the body or vertical portion thereof, is provided with one or more series of secondary air admission ports 2% which extend longitudinally of the pot burner and are associated with a deflector lip 2| of ring shape disposed parallel to the ring 20 and inwardly of the same in spaced relation and welded or otherwise affixed by an outturned attachment flange Zia to the interior of the forward end of peripheral wall l6.

Our combination pilot and vaporizing device is mounted in the upper and rearward portion of the horizontal burner illustrated in Figures 1 to 3, and in general comprises a substantially closed casing provided with a bottom for reception of liquid fuel and a top provided with a multiplicity of air inlet ports or apertures adapted to direct jets of air downwardly against the vaporizing fuel. As shown the top of said casing is formed by a section or portion lBa: of the peripheral wall of the pot burner having a multiplicity of air intake passages 16b formed therethrough and preferably, but not necessarily, being of smaller diameter and more numerous and in closer spaced relationship than the other air intake passages formed in other portions of the circumferential wall Hi. The remainder of the pilot and vaporizing casing is formed by a receptacle shell horizontally disposed in the upper portion of the pot and having upwardl diverging side walls 22a, vertical end walls 22b, and a bottom 220. The end walls 221) are arcuately and convexly shaped at their upper edges to conform to the cylindrical inner periphery of pot l6 and are secured flush against the upper portion ,of the pot casing by suitable means such as angled retaining flanges 2201 which may be integrally formed from the end walls or may be in the form of angle irons welded or otherwise secured thereto. The casing adjacent the top of the burner is provided with longitudinal passages 23 extending in the form now described throughout the length of the side walls 22a and conveniently formed by constructing the side walls short of engagement with the top of the casing formed by the section I60: of the circumferential wall [6 of the pot. Thus in this form of the invention, discharge of vapors and gases from within the pilot and vaporizing casing takes place through the longitudinal passages 23 extending substantially the full length of the casing, and directing such Vapors and gases laterally and in opposite directions from the casing and circumferentially of the burner pot in close relation to the inner peripheral wall of the pot.

Provision for lighting the pilot burner is suitably made as by an aperture in the section I61: of the circumferential wall 16 of the pot provided with an upstanding neck 24 which extends through the outer cylindrical casing H and as is shown, is closed b plug or cap 24a associated therewith.

A fuel conduit 25 extends through the exterior wall of the heating device and within cylindrical casing l l and communicates with the interior of the lower portion of the casing adjacent preferably the rear or outer end thereof, a suitable fitting 25a being provided, as shown, for threaded connection with the extremity of conduit 25. An automatic, adjustable, constant level or constant flow valve 21 of conventional type is illustrated as interposed in the fuel supply conduit 25 exteriorly of the burner and heating device to which the burner is applied, this valve being of any suitable well known type adapted to be set in a plurality of positions to maintain flow or level of fuel within the vaporizer and pilot housing at a pilot setting and various low and high flame settings.

As shown, the exterior wall of the furnace or heating device i3 is provided with a removable plate l3a disposed substantially centrally of cylindrical casing II and provided with a relatively large air intake aperture l3b. In many installations, a booster fan 28 is utilized with our structure and may be conveniently mounted on plate 30; for setting up a draft of air inwardly through the annular air passage defined between cylindrical casing II and burner casing Hi. It will of course, be understood that in many installations, a booster fan is not required or desirable.

In operation with the flow or constant level valve 21 adjusted for pilot setting, oil or other liquid fuel is delivered to the bottom 220 of the pilot and vaporizing receptacle maintaining a substantially constant level for pilot purposes. The ignition of the fuel is effected by dropping a fragment of burning paper or the like through the lighting neck 24 into the vaporizing casing. Air is then supplied through the multiplicity of air admission ports I61) in the top of the vaporizing casing provided by the section of the burner Wall Him to hydroxylize the vaporized fuel in quantities very nearly sufiicient for pilot combustion. The air is directed downwardly through ports l6b in the top of the vaporizing casing, in the form of jets against the upwardly rising fuel vapors and the mixture burns as it discharges from the longitudinal upper passages 23 through the sidewalls of the pilot and vaporizing casing where secondary air is admitted to the mixture through air supplied to the burner casing from the multiplicity of spaced radial main air ports [611.

Thus, a very complete combustion of a relatively small amount of fuel vaporized at pilot setting, is obtained in the upper portion of the horizontal burner, the flames discharging from the pilot casing laterally thereof, in opposite directions and circumferentially outward and downward and serving to very efficiently and uniformly heat the interior of the pot burner.

When the valve 21 is adjusted to maintain the fuel level within the receptable of the vaporizing housing at a level above pilot setting, the air admitted to the vaporizing casing through the ports lBb in the top thereof, is inadequate to support combustion but is directed downwardly in jets very efiiciently admixing with the upwardly rising vapors and producing a hydroxylized admixture which discharges as indicated by the arrows in Fig. 3 laterally from the vaporizing casing in opposite directions, circumferentially of the horizontal burner pot and guided by the peripheral wall [6 of the pot outwardly and downwardly. This mixture is fficiently supplied with additional air furnished to the interior of the pot burner through the multiplicity of primary air ports Mia and at the lower flame settings above pilot setting, will burn at least partially within excepts the 'burner casing withwhat is'kn'own as-a'low flame; 1

At high flame setting with the level of liquid fuel in the vaporizing casing disposed some distance above the bottom 220, the primary air supply furnished by the multiplicity of ports 16b in the top of the vaporizing casing, with the relatively large additional primary air supply furnished by the main primary air ports I6a in the circumferential wall It of the burner, is not adequate to support combustion within the interior of the burner. Secondary supply of air is furnished at the inner-or open end of the burner through th'e'multiplicity ofportsttb in air'su'pply ring 20 and this air is directed inwardly towards the axial portion of the interior of the burner by means of the deflectionring 2|, very efficie'ntly mixingwith the'hydroxylized mixture and producing'combustion outwar'dlyof'the flame ring [8.

With most horizontal pot type burner constructions, it has been difficult to obtain adequate temperatures in the upper portion of the burner pot for producing efficient combustion and proper mixture of the vaporized fuel and combustionsupporting air. With our improved structure the pilot burning and low flame burnings of the device produce adequate temperatures within the upper portion of the horizontal burner and materially improve combustion efficiency and elimination of carbon in the upper portion of the burner. Furthermore, this construction provides for a very efficient circulation and admixture of the hydroxylized fuel from the vaporizing casing in heating operation of the burner with the primary and secondary main air supplies.

In most vaporizing and pilot constructions for horizontal burners, the vaporized fuel has been discharged from the axial or core portion of the burner casing rather than from the upper portion thereof and has not been distributed circumferentiall within the inner periphery of the cylindrical burner wall. We have obtained improved results in mixture of the vaporized fuel with the air supply and in proper heating of the entire interior of the burner casing with our improved structure.

In Figs. 4 and 5, a somewhat different form of our invention is illustrated associated with a pot type burner and heating device or floor furnace, both of similar construction to the form previously described. The parts of the heating device and pot type burner are accordingly, numbered similarly to the form illustrated in Figs. 1 to 3 inclusive.

In this second form of our combination pilot and vaporizing device, we provide a casing generally similar to the form first described and having its top covering formed by a section I63: at the top and rear portion of the circumferential wall It of the pot burner. The casing has a bottom 22c and end walls 22b similar to the casing of the form first described, the end walls at their upper edges being shaped to conform to the circumference of the section Ita: of the burner wall and secured thereto as in the form first described.

The interior of the pilot and vaporizing casing is divided into two compartments A and B by a substantially central, vertical partition 29, said partition being provided with a relatively large, inverted, U-shaped communicating aperture 29a which extends some distance above the high" fuel level of the receptacle portion of the casing. The side walls 22a of the casing are extended upwardly into abutment or substantial registration with the section 16a: of the circumferential wall or the burner thrcu'ghout 1 their screens between the rear 'end' o'f the burner and vertical partition 2 9 'of the casing, whereas at their forward; upper longitudinal edges, i the upwardly diverging walls terminate" in parallel, spaced relation to the top of the burner wall defining longitudinal discharge passages 30 as clearly shown in Fig. 5.

Inthis-form of the inventionya multiplicity 'of primary airinlet ports or aperturesdisposed-in spaced relation, are provided through the encased section we of 'thepot' wall'for c'ausingjets of air to be directed downwardly against the fuel vaporized in both chambers A and B of the vaporizing casing. In some installations it is desirable to make the apertures ltd which direct air into the secondary compartme'nt'Bm'ore numerous or of greater total area than the primary air'intake' apertures l-Bb for directionof jets of air into the compartment A. This is "found to produce an improved pilot combustion of the small quantity of fuel consumed in pilot operation, the fuel vaporizing in chamber A being initially admixed with the downwardly directed jets of primary air and the mixture thereafter passing through the communicating passage 29a into chamber B and there, being further admixed with vaporizing fuel and a greater supply of air. The subsequent mixture then rises and is discharged laterally from the opposite upwardly diverging sides of the casing and burns in pilot setting as it discharges circumferentially in opposite directions at the top of the horizontal burner.

What is claimedis:

l. A combination pilot and vaporizing device for pot type liquid fuel burners of the structure having a substantially closed end and an opposite open flame discharge end and having a peripheral wall provided with a multiplicity of spaced air inlet passages extending therethrough, comprising a substantially closed housing the top portion of which is formed by a portion of the peripheral wall of said pot including a number of said passages and other portions of which are formed by a receptacle mounted against said top portion, said receptacle having a bottom portion for receiving fuel adapted to be connected with a source of fuel supply and having discharge passages in the side portions thereof adjacent said top portion said passages being adapted to discharge a vaporized mixture at opposite sides of said housing and in opposite directions in the interior of said pot.

2. In a horizontal, pot type liquid fuel burner, a horizontally disposed burner pot having an open end and a peripheral wall, said wall having a plurality of circumferentially and longitudinally spaced air inlet apertures therein, a vaporizing housing comprising a section of the top of said peripheral wall provided with a number of said air inlet apertures and a receptacle-like casing within said pot and secured against said section of said peripheral wall, said casing having discharge apertures adjacent the top of said pot for directing a vaporized mixture to the interior of said pot, a fuel supply conduit communicating with the lower portion of said casing and means for controlling the level of fuel at the bottom of said casing.

3. The structure set forth in claim 2 and a substantially vertical partition dividing the interior of said casing into two communicating chambers and the discharge apertures of said casing being formed in the one of said chambers remote from said fuel supply conduit.

4. A combination pilot and vaporizing device for horizontal, pot type liquid fuel burners having an open end comprising a relatively small housing adapted to be mounted within the burner and extending to the upper part of the interior thereof and spaced from the open end thereof, said housing including a bottom, end walls and a top provided with a plurality of air inlet ports spaced and distributed therein, adapted to direct jets of air downwardly, said casing having a substantially vertical partition therein defining two vaporizing and mixing chambers, means for delivering a liquid fuel to the interior of said casing into one of said chambers, said partition having an aperture in the lower portion thereof and that one of said chambers into which liquid fuel is not delivered by said delivering means having laterally extending discharge apertures through opposite sides of said peripheral Wall for discharging a vaporized mixture at the top of said burner pot in opposite directions.

EDWARD H. STEMPEL. MARCUS L. NELSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,162,844 Jenson June 20, 1939 2,348,721 Breese et a1 May 16, 1944 2,386,556 Huston Oct. 9, 1945 2,393,176 Livar et al Jan. 15, 1946 2,418,709 Hayter Apr. 8, 1947 2,460,013 Huston Jan. 25, 1949 2,460,014 Huston et a1. Jan. 25, 1949 

